Beyond feast and famine: Cultivating hydrodynamic oxygenic photogranules with better performances under permanent feast regime.

Oxygenic photogranules (OPGs) are currently obtained in permanent famine or cyclic feast-famine regimes. Whether photogranulation occurs under a permanent feast regime and how these regimes impact OPGs are unknown. Herein, the three regimes, each applied in two replicate hydrodynamic reactors, were established by different feeding frequencies. Results showed that OPGs were successfully cultivated in all regimes after 24-36 days of photogranulation phases with similar microbial community functions, including filamentous gliding, extracellular polymeric substances production, and carbon/nitrogen metabolism. The OPGs were then operated under the same sequencing batch mode and all achieved efficient removal of chemical oxygen demand (>91 %), ammonium (>96 %), and total nitrogen (>76 %) after different adaptation periods (19-41 days). Notably, the permanent feast regime obtained OPGs with the best physicochemical properties, the shortest adaptation period, and the lowest effluent turbidity, thus representing a novel means of hydrodynamic cultivating OPGs with better performances for sustainable wastewater treatment.

[Identification study of raw oyster and calcined ostreae concha].

OBJECTIVE: To identify the differences in characteristics of raw oyster and oysters calcined under different temperatures. METHODS: Identified raw oyster, oysters calcined under different temperatures and calcium carbonate, calcium oxide by differential thermal analysis, infrared spectroscopy and X-ray diffraction analysis. RESULTS: Composition of calcined oysters was closer to calcium carbonate than raw oyster. CONCLUSION: The fingerprints are established and identify raw oyster and calcined oysters.